誰かが、例えば、羊とか馬を市場に出ているもので等しい価値があると考えるものと交換することが出来たのである。

who

indicates a question (sometimes rhetorical); or; whether or not; some- (e.g. something, someone); indicates doubt, uncertainty, etc.; emphatic prefix; suffix forming adjectives or adverbs; in that way

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

for example; e.g.

sheep (Ovis aries)

among other things; such things as; or something like that

horse; promoted bishop

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

(the) market (as a concept)

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

to leave; to exit; to go out; to come out; to get out; to leave (on a journey); to depart; to start out; to set out; to move forward; to come to; to get to; to lead to; to reach; to appear; to come out; to emerge; to surface; to come forth; to turn up; to be found; to be detected; to be discovered; to be exposed; to show; to be exhibited; to be on display; to appear (in print); to be published; to be announced; to be issued; to be listed; to come out; to attend; to participate; to take part; to enter (an event); to play in; to perform; to be stated; to be expressed; to come up; to be brought up; to be raised; to sell; to exceed; to go over; to stick out; to protrude; to break out; to occur; to start; to originate; to be produced; to come from; to be derived from; to be given; to get; to receive; to be offered; to be provided; to be presented; to be submitted; to be handed in; to be turned in; to be paid; to answer (phone, door, etc.); to get; to assume (an attitude); to act; to behave; to pick up (speed, etc.); to gain; to flow (e.g. tears); to run; to bleed; to graduate

person

be; is; indicates past or completed action; indicates light imperative

equal; similar; like; equivalent

value; worth; merit

to be (usu. of inanimate objects); to exist; to live; to have; to be located; to be equipped with; to happen; to come about

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

to think about; to take into consideration; to ponder; to reflect; to try to come at a conclusion; to think over (something); to intend; to decide (to do); to plan; to come up with; to devise; to scheme; to predict; to anticipate; to expect; to suspect; to doubt; to consider (somebody to be something); to look on

exchange; interchange; switching; reciprocity; barter; substitution; replacement; clearing (of checks, cheques)

thing; matter; incident; occurrence; event; something serious; trouble; crisis; circumstances; situation; state of affairs; work; business; affair; after an inflectable word, creates a noun phrase indicating something the speaker does not feel close to; nominalizing suffix; pretending to ...; playing make-believe ...; alias; aka; nickname; alternative name; also known as

to be able (in a position) to do; to be up to the task; to be ready; to be completed; to be made; to be built; to be good at; to be permitted (to do); to become intimate; to take up (with somebody); to grow; to be raised; to become pregnant

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

a certain ...; some ...